Data collected during 336 hr. of observation with ten Zebu cattle were examined to assess the extent of variation between these animals and the extent to which these animals conform to the general herd behaviour. A further use was made of the data to discuss the effects of individual animal behaviour on the numbers of animals it is necessary to observe.

1. A pilot survey was designed to provide information on the mechanical conditions and fuel consumptions of vaporizing oil tractors, on their operation in the field and on the technique required to obtain such data.

2. Two areas were chosen offering a contrast in soil and farming types. A sampling frame was prepared for each area in which the farms were grouped according to the number of tractors.

The effect of different amounts of irrigation water on the salts in Gezira soil has been studied by comparison of different rotations in two long-term experiments at the Gezira Research Farm. The conclusion is drawn that none of the rotations studied shows any evidence of salts rising or accumulating in the profile. There is some evidence of a removal of salts from a 6 ft. profile.

The investigation shows that when ammonium sulphate or oil cake was applied to cropped rice soils 4 weeks after transplantation, a considerable amount of the added nitrogen was lost as gas. This loss, however, was less than the loss that took place when the crop was absent. Placement of ammonium sulphate 3 in. below the soil surface reduced the loss of nitrogen, but did not significantly increase the crop yield. Gases evolved from cropped rice soils, whether unmanured or treated with ammonium sulphate, were free from hydrogen and contained practically no methane, while those formed in the uncropped soil under similar treatments contained large volumes of these two gases.

Semen samples were collected from twelve fattailed rams of two breeds (nine Ossimi and three Rahmani), by the use of an artificial vagina. They were kept under natural conditions at Cairo, Egypt (30° N.). Three collections were made each month throughout one year (1951–2).

In the inbred lines of a flock of Brown Leghorns, it was noted that the line means for albumen weight ranked in the same order as those for shank width. The parallelism was not due to the large differences in body weight existing between the lines.

It was established that variations in albumen weight were more closely associated with changes in shank width than were those of yolk weight. It is possible, but not definitely established, that shell weight follows the behaviour of albumen in this respect.

1. The relationship existing between the gross digestible energy content and the chemical composition of 24 hays has been studied with nine Cheviot wether lambs over a period of 8 months.

2. Each hay was fed to a group of three lambs for a 10-day preliminary and 10-day collection period. Faeces and urine were collected in metabolism crates.

1. Dissections were carried out on lambs, and the skin was found to be supplied by numerous small arteries fairly evenly distributed, but often in series along the body. In several instances these arterial trunks were traced back through the body muscles to various main arteries.

1. The rate of passage of ova down the Fallopian tubes in the pig has been checked on eighteen living sows by laparotomy and in fifteen sows and gilts at autopsy.

2. Both sets of observations suggest that the ova enter the uterus between 24 and 48 hr. after ovulation instead of 72 hr. as suggested by earlier workers.

3. It is suggested that the rapid passage of ova through the Fallopian tubes of the pig may be facilitated by the progesterone from the large number of corpora lutea in the ovaries of the pig.

A study has been made of the reactions of three breeds of sheep (Blackface, Cheviot and Wiltshire) to four different environments. Evidence was obtained that these breeds react differently to these different environments. No changes in rank occurred but the Blackfaces grew relatively faster on a good plane of nutrition than the other two breeds. Their wool production on a sample area was also relatively greater, due primarily to an increase in diameter of the non-medullated fibres. These differences indicate fundamental physiological differences in reaction to environment.

1. The rectal temperatures of three 4-month-old Ayrshire bull calves were measured in individual 6 hr. daily exposures to 15, 20, 25, 30, 35 and 40° C. dry-bulb temperature at low humidity (17 mg./l. absolute humidity) and to 30, 35 and 40° C. at high humidity (7 mg./l. saturation deficit). The experiments on each animal lasted 45 consecutive days and consisted of five replications of these nine environmental conditions. Measurements of rectal temperature were made every 5 min.

2. The rectal temperatures of the animals rose with increasing environmental temperature and humidity.

1. The skin temperatures at each of eight positions on the trunks of three 4-month-old Ayrshire bull calves were measured at 5 min. intervals in individual 6 hr. daily exposures to dry-bulb temperatures of 15, 20, 25, 30, 35 and 40° C. at 17 mg./l. absolute humidity, and 30, 35 and 40° C. at 7 mg./l. saturation deficit in a modified form of Latin square arrangement of environmental temperature. The schedule of experiments on each calf lasted 45 consecutive days and consisted of five replications of each of the nine environmental conditions.

2. The skin temperatures of the calves all rose with increasing environmental temperature, humidity and time of exposure.

1. The temperature of the surface of the scrota of three 4-month-old Ayrshire calves has been measured in environments of 15, 20, 25, 30, 35 and 40° C. at a low humidity of 17 mg./l. absolute humidity and in environments of 30, 35 and 40° C. at a high humidity of 7 mg./l. saturation deficit. Five replicate experiments were performed at each environment on each animal and the animals were exposed to each environment for 6 hr.; measurements of scrotal temperature were made once every 5 min.

2. The scrotal surface temperature increased with increasing environmental temperature ranging from 32° C. at 15° C. to 39° C. at 40° C. The rates of increase in scrotal surface temperature with environmental temperature were curvilinear for two of the animals and rectilinear for the other. For the two whose rates of increase were curvilinear the rate of increase was constant at 0·2° C./° C. environmental temperature in the range 15–25° C.

1. The surface temperature of the right and left ears of 4-month-old Ayrshire bull calves subjected to temperatures of 15, 20, 25, 30, 35 and 40° C. at a low humidity of 17 mg./l. absolute humidity and to 30, 35 and 40° C. at a high humidity of 7 mg./l. saturation deficit, have been measured in a climatic room.

2. From 20 to 40° C. at both humidities, but excluding 40° C. at high humidity, the ear-surface temperatures behaved exactly as did the mean surface temperature of the trunk as expressed in the relation

1. The two spring oat varieties, Argentine and Victory, and the two winter varieties, Grey Winter and Black Winter, have 0.10, 0.07, 1.57 and 0.41% pollen mother cells with irregular meioses respectively.

2. F1Victory x Argentine had 3.43% of irregular meioses, and F1. Grey Winter x Black Winter 1.58%.